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Hi guy's ,i just woke up a old project and i just got a 160VA , 2x9V transformer and 8 pcs of 22000uF caps for the powerboardand this weekend i was thinking to power'it up but one issue is between that ,i've been reading a lot of material about this amp but one thing i don't get is how to set bias or Dc offset .If i need to run that with a load i have a 4 Ohm's dummyload that can handle 200W if that helps and now i hopingyou guy's can explain for a another (dummy) how to perform a correct adjustment for this.I took a picture of one the boards.

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Hi Gregg,the power transistors that i know to 100% are original (0302 & 0281) are with'in 3mA matched andthe 716 & 756 are matched to 2mA,the other i'm not sure if they are org or fake but they are very close to each other (with'in 4mA ) on all and of the otheri bought in pack of 50 so it was a lot of measuring before i was satisfied.So what is my biggest concern now ? is that to set DC offset ? or is it bias to set in a class A ?

the other i'm not sure if they are org or fake but they are very close to each other (with'in 4mA ) on all and of the other

To check if a transistor is real, the only way is to put it at about 70% of maximum rated voltage and about 70% of rating power disipation with resonablly large cooling, also should be directly connected to heatsink with heat sink grease for large transistors.

For to-92 transistors about 300-400mW of load is a good target. I can share my transistor testing schematic if your interested

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